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  • richardmitnick 11:39 am on April 27, 2017 Permalink | Reply
    Tags: MIT, Monica Pham,   

    From MIT: Women in STEM- “Monica Pham: Advancing nuclear power and empowering girls” 

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    April 21, 2017
    Leda Zimmerman | Department of Nuclear Science and Engineering

    3
    “I want to empower girls to feel they belong in these fields,” says Monica Pham, a sophomore in nuclear science and engineering. Photo: Susan Young

    Sophomore researches fusion energy and promotes STEM opportunities for young women.

    When she was 16, Monica Pham mapped out her future. “My chemistry teacher was talking about how atoms could generate unlimited power,” Pham recalls. “I asked her what kind of person worked in this field, and when she said a nuclear engineer, I decided that’s what I wanted to be.”

    Today, as a college sophomore pursuing a degree in the Department of Nuclear Science and Engineering (NSE), Pham could not be happier with her decision. “That weird, defining moment in high school has worked out well for me, because with my interests in energy and engineering, NSE is a really great fit.”

    In addition to her full plate of NSE classes, such as 22.01 (Introduction to Nuclear Engineering and Ionizing Radiation) and 22.06 (Engineering of Nuclear Systems), Pham is engaged in research at the Collaboration for Science and Technology with Accelerators and Radiation (CSTAR), a joint laboratory of NSE and the Plasma Science and Fusion Center.

    2
    http://cstar.mit.edu/home.php

    “I remembered touring the CSTAR facility during freshman pre-orientation, and thought this would be a great way to get my first real experience in nuclear engineering,” Pham says.

    Pham’s project, one of a number at CSTAR, is under the supervision of assistant professor Zachary Hartwig, and involves the development of a system for diagnosing materials used in tokamaks — nuclear fusion reactors.

    5
    Interior of the Alcator C-Mod tokamak. MIT tokamak. MIT Plasma Science and Fusion Center

    Fusion energy harnesses the power of super-hot plasma, the fuel of stars, to generate enormous amounts of energy. Tokamaks confine and control plasma through the use of magnetic fields.

    Before fusion energy can become a viable source of energy, critical issues must be addressed. Hartwig’s research, part of a five-year study devised by NSE Professor Dennis Whyte, focuses on some central questions: What are the potentially destructive impacts of plasma on tokamak components, and can these effects be assessed inside the fiery furnace of a typically inaccessible tokamak chamber?

    This is where Pham comes in. She is part of a team using a particle accelerator to blast a beam of atomic particles at materials used in tokamak components. This research is an initial step in developing a full-scale diagnostic technique to measure the impacts of harsh conditions on plasma-facing components in a major fusion facility.

    “Because plasma is kind of crazy, there is a lot of erosion and deposition to these materials in a tokamak,” she says “Previous diagnostic techniques are all ex situ — you have to take components out of the chamber afterwards to see how plasma affected them — so this technique is novel and could really help with new fusion reactor designs.”

    Some days Pham will help assemble the experiment, setting up the small metallic targets at the end of the accelerator beamline. Other days, she collects data from the detectors, plotting the intensity of the yield of atomic particles such as gamma radiation against the intensity of the accelerator beam.

    “I’m learning a lot about how to set up and run experiments from them,” she says. “It’s both challenging and fun, especially when we have to troubleshoot an experiment that isn’t working as planned.”

    After four straight terms on this project, Pham looks forward to the potential publication of research in which she has been involved. “One of the graduate students hopes to publish, including data I collected last year,” she says. “It would be kind of cool to be an undergraduate and a co-author.”

    When not in class or in the laboratory, Pham makes time for the MIT chapter of the Society of Women Engineers. As festival chair, she sets up workshops and activities to engage girls and young women in science and engineering.

    Pham recalls times during secondary school when she “was not taken as seriously as boys who wanted to go into engineering,” she says. “People would say to me, ‘Are you sure you want to do that; it seems pretty hard.’” As a result of these experiences, she says, “I want to empower girls to feel they belong in these fields.”

    At such venues as the Cambridge Science Festival, and the USA Science and Engineering Festival in Washington, Pham runs open houses intended to introduce girls both to fun science, like using lemon juice to polish a penny, and to female science and engineering role models such as herself. “Some kids ask what it’s like to be a woman engineer or an MIT student, and I tell them it’s really cool,” she says.

    She has proof this outreach makes a difference. “One time I was helping an eight-year-old girl build a mini-catapult, and she turned to me and said, ‘I was going to ask for a robot for Christmas and now I want to build a robot myself,’” says Pham. “It was an amazing moment, and showed me my efforts could really pay off.”

    See the full article here .

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  • richardmitnick 6:59 am on April 25, 2017 Permalink | Reply
    Tags: , , MIT, Nile River   

    From MIT: “Nile faces greater variability” 

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    April 24, 2017
    David L. Chandler

    1
    Researchers at MIT have found that climate change may drastically increase the variability in Nile’s annual output.

    Climate change could lead to overall increase in river flow, but more droughts and floods, study shows.

    The unpredictable annual flow of the Nile River is legendary, as evidenced by the story of Joseph and the Pharaoh, whose dream foretold seven years of abundance followed by seven years of famine in a land whose agriculture was, and still is, utterly dependent on that flow. Now, researchers at MIT have found that climate change may drastically increase the variability in Nile’s annual output.

    Being able to predict the amount of flow variability, and even to forecast likely years of reduced flow, will become ever more important as the population of the Nile River basin, primarily in Egypt, Sudan, and Ethiopia, is expected to double by 2050, reaching nearly 1 billion. The new study, based on a variety of global climate models and records of rainfall and flow rates over the last half-century, projects an increase of 50 percent in the amount of flow variation from year to year.

    The study, published in the journal Nature Climate Change, was carried out by professor of civil and environmental engineering Elfatih Eltahir and postdoc Mohamed Siam. They found that as a result of a warming climate, there will be an increase in the intensity and duration of the Pacific Ocean phenomenon known as the El Niño/La Niña cycle, which they had previously shown is strongly connected to annual rainfall variations in the Ethiopian highlands and adjacent eastern Nile basins. These regions are the primary sources of the Nile’s waters, accounting for some 80 percent of the river’s total flow.

    The cycle of the Nile’s floods has been “of interest to human civilization for millennia,” says Eltahir, the Breene M. Kerr Professor of Hydrology and Climate. Originally, the correlation he showed between the El Niño/La Niña cycle and Ethiopian rainfall had been aimed at helping with seasonal and short-term predictions of the river’s flow, for planning storage and releases from the river’s many dams and reservoirs. The new analysis is expected to provide useful information for much longer-term strategies for placement and operation of new and existing dams, including Africa’s largest, the Grand Ethiopian Renaissance Dam, now under construction near the Ethiopia-Sudan border.

    While there has been controversy about that dam, and especially about how the filling of its reservoir will be coordinated with downstream nations, Eltahir says this study points to the importance of focusing on the potential impacts of climate change and rapid population growth as the most significant drivers of environmental change in the Nile basin. “We think that climate change is pointing to the need for more storage capacity in the future,” he says. “The real issues facing the Nile are bigger than that one controversy surrounding that dam.”

    Using a variety of global circulation models under “business as usual” scenarios, assuming that major reductions in greenhouse gas emissions do not take place, the study finds that the changing rainfall patterns would likely lead to an average increase of the Nile’s annual flow of 10 to 15 percent. That is, it would grow from its present 80 cubic kilometers per year to about 92 or more cubic kilometers per year averaged over the 21st century, compared to the 20th century average.

    The findings also suggest that there will be substantially fewer “normal” years, with flows between 70 and 100 cubic kilometers per year. There will also be many more extreme years with flows greater than 100, and more years of drought. (Statistically, the variability is measured as the standard deviation of the annual flow rates, which is the number that is expected to see a 50 percent rise).

    The pattern has in fact played out over the last two years — 2015, an intense El Niño year, saw drought conditions in the Nile basin, while the La Niña year of 2016 saw high flooding. “It’s not abstract,” Eltahir says. “This is happening now.”

    As with Joseph’s advice to Pharaoh, the knowledge of such likely changes can help planners to be prepared, in this case by storing water in huge reservoirs to be released when it is really needed.

    “Too often we focus on how climate change might influence average conditions, to the exclusion of thinking about variability,” says Ben Zaitchik, an associate professor of earth and planetary sciences at Johns Hopkins University, who was not involved in this work. “That can be a real problem for a place like the Eastern Nile basin, where average rainfall and streamflow might increase with climate change, suggesting that water will be plentiful. But if variability increases as well, then there could be as frequent or more frequent stress events, and significant planning — in infrastructure or management strategies — might be required to ensure water security.”

    Already, Eltahir’s earlier work on the El Niño/La Niña correlation with Nile flow is making an impact. “It’s used operationally in the region now in issuing seasonal flood forecasts, with a significant lead time that gives water resources engineers enough time to react. Before, you had no idea,” he says adding that he hopes the new information will enable even better long-term planning. “By this work, we at least reduce some of the uncertainty.”

    See the full article here .

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  • richardmitnick 12:48 pm on April 14, 2017 Permalink | Reply
    Tags: , Fog harvesting, MIT, , water everywhere … even in the air   

    From MIT: “Water, water everywhere … even in the air” 

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    April 14, 2017
    David Chandler

    1
    This proof-of-concept device, built at MIT, demonstrates a new system for extracting drinking water from the air. The sequence of images at right shows how droplets of water accumulate over time as the inside temperature increases while exposed to the sun. Images courtesy of the researchers

    Scientists discover a way to harvest fresh water from air, including in arid regions.

    Severe water shortages already affect many regions around the world, and are expected to get much worse as the population grows and the climate heats up. But a new technology developed by scientists at MIT and the University of California at Berkeley could provide a novel way of obtaining clean, fresh water almost anywhere on Earth, by drawing water directly from moisture in the air even in the driest of locations.

    Technologies exist for extracting water from very moist air, such as “fog harvesting” systems that have been deployed in a number of coastal locations. And there are very expensive ways of removing moisture from drier air. But the new method is the first that has potential for widespread use in virtually any location, regardless of humidity levels, the researchers say. They have developed a completely passive system that is based on a foam-like material that draws moisture into its pores and is powered entirely by solar heat.

    The findings are reported in the journal Science by a team including MIT associate professor of mechanical engineering Evelyn Wang, MIT postdoc Sameer Rao, graduate student Hyunho Kim, research scientists Sungwoo Yang and Shankar Narayanan (currently at Rensselaer Polytechnic Institute), and alumnus Ari Umans SM ’15. The Berkeley co-authors include graduate student Eugene Kapustin, project scientist Hiroyasu Furukawa, and professor of chemistry Omar Yaghi.

    Fog harvesting, which is being used in many countries including Chile and Morocco, requires very moist air, with a relative humidity of 100 percent, explains Wang, who is the Gail E. Kendall Professor at MIT. But such water-saturated air is only common in very limited regions. Another method of obtaining water in dry regions is called dew harvesting, in which a surface is chilled so that water will condense on it, as it does on the outside of a cold glass on a hot summer day, but it “is extremely energy intensive” to keep the surface cool, she says, and even then the method may not work at a relative humidity lower than about 50 percent. The new system does not have these limitations.

    For drier air than that, which is commonplace in arid regions around the world, no previous technology provided a practical way of getting water. “There are desert areas around the world with around 20 percent humidity,” where potable water is a pressing need, “but there really hasn’t been a technology available that could fill” that need, Wang says. The new system, by contrast, is “completely passive — all you need is sunlight,” with no need for an outside energy supply and no moving parts.

    In fact, the system doesn’t even require sunlight — all it needs is some source of heat, which could even be a wood fire. “There are a lot of places where there is biomass available to burn and where water is scarce,” Rao says.

    The key to the new system lies in the porous material itself, which is part of a family of compounds known as metal-organic frameworks (MOFs). Invented by Yaghi two decades ago, these compounds form a kind of sponge-like configuration with large internal surface areas. By tuning the exact chemical composition of the MOF these surfaces can be made hydrophilic, or water-attracting. The team found that when this material is placed between a top surface that is painted black to absorb solar heat, and a lower surface that is kept at the same temperature as the outside air, water is released from the pores as vapor and is naturally driven by the temperature and concentration difference to drip down as liquid and collect on the cooler lower surface.

    Tests showed that one kilogram (just over two pounds) of the material could collect about three quarts of fresh water per day, about enough to supply drinking water for one person, from very dry air with a humidity of just 20 percent. Such systems would only require attention a few times a day to collect the water, open the device to let in fresh air, and begin the next cycle.

    What’s more, MOFs can be made by combining many different metals with any of hundreds of organic compounds, yielding a virtually limitless variety of different compositions, which can be “tuned” to meet a particular need. So far more than 20,000 varieties of MOFs have been made.

    “By carefully designing this material, we can have surface properties that can absorb water very efficiently at 50 percent humidity, but with a different design, it can work at 30 percent,” says Kim. “By selecting the right materials, we can make it suitable for different conditions. Eventually we can harvest water from the entire spectrum” of water concentrations, he says.

    Yaghi, who is the founding director of the Berkeley Global Science Institute, says “One vision for the future is to have water off-grid, where you have a device at home running on ambient solar for delivering water that satisfies the needs of a household. … To me, that will be made possible because of this experiment. I call it personalized water.”

    While these initial experiments have proved that the concept can work, the team says there is more work to be done in refining the design and searching for even more effective varieties of MOFs. The present version can collect water up to about 25 percent of its own weight, but with further tuning they think that proportion could be at least doubled.

    “Wow, that is an amazing technology,” says Yang Yang, a professor of engineering at the University of California at Los Angeles, who was not involved in this work. “It will have a tremendous scientific and technical impact on renewable and sustainable resources, such as water and solar energy.”

    The work was supported in part by ARPA-E, a program of the U.S. Department of Energy.

    See the full article here .

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  • richardmitnick 2:52 pm on April 4, 2017 Permalink | Reply
    Tags: , MIT, ,   

    From MIT: “Seeing black holes and beyond” 

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    April 4, 2017
    Haystack Observatory

    A powerful new array of radio telescopes is being deployed for the first time this week, as the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile joins a global network of antennas poised to make some of the highest resolution images that astronomers have ever obtained.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    The improved level of detail is equivalent to being able to count the stitches on a baseball from 8,000 miles away.

    Scientists at MIT and other institutions are using a method called VLBI (Very Long Baseline Interferometry) to link a group of radio telescopes spread across the globe into what is, in effect, a telescope the size of our planet. Although the technique of VLBI is not new, scientists have just recently begun extending it to millimeter wavelengths to achieve a further boost in resolving power. And now, the addition of ALMA to global VLBI arrays is providing an unprecedented leap in VLBI capabilities.

    European VLBI

    The inclusion of ALMA was recently made possible through the ALMA Phasing Project (APP), an international effort led by the MIT Haystack Observatory in Westford, Massachusetts, and principal investigator Sheperd Doeleman, now at the Harvard–Smithsonian Center for Astrophysics.

    Before this project, the ALMA dishes worked with each other to make observations as a single array; now, the APP has achieved the synchronizing, or “phasing,” of up to 61 ALMA antennas to function as a single, highly sensitive radio antenna — the most antennas ever phased together. To achieve this, the APP team developed custom software and installed several new hardware components at ALMA, including a hydrogen maser (a type of ultraprecise atomic clock), a set of very-high-speed data reformatters, and a fiber optic system for transporting an 8 gigabyte-per-second data stream to four ultrafast data recorders (the Haystack-designed Mark6). The culmination of these efforts is an order-of-magnitude increase in the sensitivity of the world’s millimeter VLBI networks, and a dramatic boost in their ability to create detailed images of sources that previously appeared as mere points of light.

    “A great many people have worked very hard over the past several years to make this dream a reality,” says Geoff Crew, software lead for the APP. “ALMA VLBI is truly going to be transformative for our science.”

    One of the goals of these new technological innovations is to image a black hole. This month, two international organizations are making observations that will allow scientists to construct such an image for the very first time. And the portrait they’re attempting to capture is close to home: Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way.

    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    So much data will be collected during the two observation periods that it’s faster to fly them to Haystack than it would be to transmit them electronically. Petabytes of data will be flown from telescopes around the world to Haystack for correlation and processing before images of the black hole can be created. Correlation, which registers the data from all participating telescopes to account for the different arrival times of the radio waves at each site, is done using a specialized bank of powerful computers. MIT Haystack is one of the few radio science facilities worldwide with the necessary technology and expertise to correlate this amount of data. Additional correlation for these sessions is being done at the Max Planck Institute for Radio Astronomy in Bonn, Germany.

    Two observing sessions are taking place. The GMVA (Global mm-VLBI Array) session will observe a variety of sources at a wavelength of 3 millimeters, including Sgr A* and other active galactic nuclei, and the EHT (Event Horizon Telescope) session will observe Sgr A* as well as the supermassive black hole at the center of a nearby galaxy, M87, at a wavelength of 1.3 millimeters. The EHT team includes researchers from MIT’s Haystack Observatory and MIT Computer Science and Artificial Intelligence Laboratory (CSAIL), working with the Harvard-Smithsonian Center for Astrophysics and many other organizations.

    Global mm-VLBI Array

    _______________________________________________________________________________________________________________________________________

    Event Horizon Telescope Array

    Event Horizon Telescope map

    The locations of the radio dishes that will be part of the Event Horizon Telescope array. Image credit: Event Horizon Telescope sites, via University of Arizona at https://www.as.arizona.edu/event-horizon-telescope.

    Arizona Radio Observatory
    Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

    ESO/APEX
    Atacama Pathfinder EXperiment (APEX)

    CARMA Array no longer in service
    Combined Array for Research in Millimeter-wave Astronomy (CARMA)

    Atacama Submillimeter Telescope Experiment (ASTE)
    Atacama Submillimeter Telescope Experiment (ASTE)

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

    IRAM NOEMA interferometer
    Institut de Radioastronomie Millimetrique (IRAM) 30m

    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano

    CfA Submillimeter Array Hawaii SAO
    Submillimeter Array Hawaii SAO

    Future Array/Telescopes

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array, Chile

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    South Pole Telescope SPTPOL
    South Pole Telescope SPTPOL

    __________________________________________________________________________________________________________________________________

    “Several factors make 1.3 mm the ideal observing wavelength for Sgr A*,” according to APP Project Scientist Vincent Fish. “At longer observing wavelengths, the source would be blurred by free electrons between us and the galactic center, and we wouldn’t have enough resolution to see the predicted black hole shadow. At shorter wavelengths, the Earth’s atmosphere absorbs most of the signal.”

    The current observations are the first in a series of groundbreaking studies in VLBI and radio interferometry that will enable dramatic new scientific discoveries. Data from the newly phased ALMA array will also allow better imaging of other distant radio sources via improved data sampling, increased angular resolution, and eventually spectral-line VLBI — observations of emissions from specific elements and molecules.

    “Phasing ALMA has opened whole new possibilities for ultra high-resolution science that will go far beyond the study of black holes,” says Lynn Matthews, commissioning scientist for the APP. “For example, we expect to be able to make movies of the gas motions around stars that are still in the process of forming and map the outflows that occur from dying stars, both at a level of detail that has never been possible before.”

    The black hole images from the data gathered this month will take months to prepare; researchers expect to publish the first results in 2018.

    The MIT Haystack Observatory team of scientists includes Geoff Crew, Vincent Fish, Michael Hecht, Lynn Matthews, Colin Lonsdale, and Sheperd Doeleman (now at the Harvard-Smithsonian Center for Astrophysics).

    The organizations of the APP are: MIT Haystack Observatory (lead organization), Harvard–Smithsonian Center for Astrophysics, Joint ALMA Observatory (Chile), National Radio Astronomy Observatory (NRAO), Max Planck Institute for Radio Astronomy (Germany), University of Concepción (Chile), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), National Astronomical Observatory of Japan (NAOJ), and Onsala Observatory (Sweden).

    See the full article here .

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  • richardmitnick 9:44 am on March 29, 2017 Permalink | Reply
    Tags: , , MIT, , ,   

    From MIT: “Progress toward a Zika vaccine” A lot of Zika News Lately 

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    March 29, 2017
    Anne Trafton

    1
    MIT researchers have devised a new vaccine candidate for the Zika virus. “It functions almost like a synthetic virus, except it’s not pathogenic and it doesn’t spread,” says postdoc Omar Khan. Image: Jose-Luis Olivares/MIT

    Researchers program RNA nanoparticles that could protect against the virus.

    Using a new strategy that can rapidly generate customized RNA vaccines, MIT researchers have devised a new vaccine candidate for the Zika virus.

    The vaccine consists of strands of genetic material known as messenger RNA, which are packaged into a nanoparticle that delivers the RNA into cells. Once inside cells, the RNA is translated into proteins that provoke an immune response from the host, but the RNA does not integrate itself into the host genome, making it potentially safer than a DNA vaccine or vaccinating with the virus itself.

    “It functions almost like a synthetic virus, except it’s not pathogenic and it doesn’t spread,” says Omar Khan, a postdoc at MIT’s Koch Institute for Integrative Cancer Research and an author of the new study. “We can control how long it’s expressed, and it’s RNA so it will never integrate into the host genome.”

    This research also yielded a new benchmark for evaluating the effectiveness of other Zika vaccine candidates, which could help others who are working toward the same goal.

    Jasdave Chahal, a postdoc at MIT’s Whitehead Institute for Biomedical Research, is the first author of the paper, which appears in Scientific Reports. The paper’s senior author is Hidde Ploegh, a former MIT biology professor and Whitehead Institute member who is now a senior investigator in the Program in Cellular and Molecular Medicine at Boston Children’s Hospital.

    Other authors of the paper are Tao Fang and Andrew Woodham, both former Whitehead Institute postdocs in the Ploegh lab; Jingjing Ling, an MIT graduate student; and Daniel Anderson, an associate professor in MIT’s Department of Chemical Engineering and a member of the Koch Institute and MIT’s Institute for Medical Engineering and Science (IMES).

    Programmable vaccines

    The MIT team first reported its new approach to programmable RNA vaccines last year. RNA vaccines are appealing because they induce host cells to produce many copies of the proteins encoded by the RNA. This provokes a stronger immune reaction than if the proteins were administered on their own. However, finding a safe and effective way to deliver these vaccines has proven challenging.

    The researchers devised an approach in which they package RNA sequences into a nanoparticle made from a branched molecule that is based on fractal-patterned dendrimers. This modified-dendrimer-RNA structure can be induced to fold over itself many times, producing a spherical particle about 150 nanometers in diameter. This is similar in size to a typical virus, allowing the particles to enter cells through the same viral entry mechanisms. In their 2016 paper, the researchers used this nanoparticle approach to generate experimental vaccines for Ebola, H1N1 influenza, and the parasite Toxoplasma gondii.

    In the new study, the researchers tackled Zika virus, which emerged as an epidemic centered in Brazil in 2015 and has since spread around the world, causing serious birth defects in babies born to infected mothers. Since the MIT method does not require working with the virus itself, the researchers believe they might be able to explore potential vaccines more rapidly than scientists pursuing a more traditional approach.

    Instead of using viral proteins or weakened forms of the virus as vaccines, which are the most common strategies, the researchers simply programmed their RNA nanoparticles with the sequences that encode Zika virus proteins. Once injected into the body, these molecules replicate themselves inside cells and instruct cells to produce the viral proteins.

    The entire process of designing, producing, and testing the vaccine in mice took less time than it took for the researchers to obtain permission to work with samples of the Zika virus, which they eventually did get.

    “That’s the beauty of it,” Chahal says. “Once we decided to do it, in two weeks we were ready to vaccinate mice. Access to virus itself was not necessary.”

    Measuring response

    When developing a vaccine, researchers usually aim to generate a response from both arms of the immune system — the adaptive arm, mediated by T cells and antibodies, and the innate arm, which is necessary to amplify the adaptive response. To measure whether an experimental vaccine has generated a strong T cell response, researchers can remove T cells from the body and then measure how they respond to fragments of the viral protein.

    Until now, researchers working on Zika vaccines have had to buy libraries of different protein fragments and then test T cells on them, which is an expensive and time-consuming process. Because the MIT researchers could generate so many T cells from their vaccinated mice, they were able to rapidly screen them against this library. They identified a sequence of eight amino acids that the activated T cells in the mouse respond to. Now that this sequence, also called an epitope, is known, other researchers can use it to test their own experimental Zika vaccines in the appropriate mouse models.

    “We can synthetically make these vaccines that are almost like infecting someone with the actual virus, and then generate an immune response and use the data from that response to help other people predict if their vaccines would work, if they bind to the same epitopes,” Khan says. The researchers hope to eventually move their Zika vaccine into tests in humans.

    “The identification and characterization of CD8 T cell epitopes in mice immunized with a Zika RNA vaccine is a very useful reference for all those working in the field of Zika vaccine development,” says Katja Fink, a principal investigator at the A*STAR Singapore Immunology Network. “RNA vaccines have received much attention in the last few years, and while the big breakthrough in humans has not been achieved yet, the technology holds promise to become a flexible platform that could provide rapid solutions for emerging viruses.”

    Fink, who was not involved in the research, added that the “initial data are promising but the Zika RNA vaccine approach described needs further testing to prove efficacy.”

    Another major area of focus for the researchers is cancer vaccines. Many scientists are working on vaccines that could program a patient’s immune system to attack tumor cells, but in order to do that, they need to know what the vaccine should target. The new MIT strategy could allow scientists to quickly generate personalized RNA vaccines based on the genetic sequence of an individual patient’s tumor cells.

    The research was funded by the National Institutes of Health, a Fujifilm/MediVector grant, the Lustgarten Foundation, a Koch Institute and Dana-Farber/Harvard Center Center Bridge Project award, the Department of Defense Office of Congressionally Directed Medical Research’s Joint Warfighter Medical Research Program, and the Cancer Center Support Grant from the National Cancer Institute.

    See the full article here .

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  • richardmitnick 1:05 pm on March 24, 2017 Permalink | Reply
    Tags: "Tree on a chip", , may be used to make small robots move., Microfluidic device generates passive hydraulic power, MIT,   

    From MIT: “Engineers design “tree-on-a-chip” 

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    March 20, 2017
    Jennifer Chu

    1
    Engineers have designed a microfluidic device they call a “tree-on-a-chip,” which mimics the pumping mechanism of trees and other plants.

    2
    Like its natural counterparts, the chip operates passively, requiring no moving parts or external pumps. It is able to pump water and sugars through the chip at a steady flow rate for several days.
    Courtesy of the researchers

    Microfluidic device generates passive hydraulic power, may be used to make small robots move.

    Trees and other plants, from towering redwoods to diminutive daisies, are nature’s hydraulic pumps. They are constantly pulling water up from their roots to the topmost leaves, and pumping sugars produced by their leaves back down to the roots. This constant stream of nutrients is shuttled through a system of tissues called xylem and phloem, which are packed together in woody, parallel conduits.

    Now engineers at MIT and their collaborators have designed a microfluidic device they call a “tree-on-a-chip,” which mimics the pumping mechanism of trees and plants. Like its natural counterparts, the chip operates passively, requiring no moving parts or external pumps. It is able to pump water and sugars through the chip at a steady flow rate for several days. The results are published this week in Nature Plants.

    Anette “Peko” Hosoi, professor and associate department head for operations in MIT’s Department of Mechanical Engineering, says the chip’s passive pumping may be leveraged as a simple hydraulic actuator for small robots. Engineers have found it difficult and expensive to make tiny, movable parts and pumps to power complex movements in small robots. The team’s new pumping mechanism may enable robots whose motions are propelled by inexpensive, sugar-powered pumps.

    “The goal of this work is cheap complexity, like one sees in nature,” Hosoi says. “It’s easy to add another leaf or xylem channel in a tree. In small robotics, everything is hard, from manufacturing, to integration, to actuation. If we could make the building blocks that enable cheap complexity, that would be super exciting. I think these [microfluidic pumps] are a step in that direction.”

    Hosoi’s co-authors on the paper are lead author Jean Comtet, a former graduate student in MIT’s Department of Mechanical Engineering; Kaare Jensen of the Technical University of Denmark; and Robert Turgeon and Abraham Stroock, both of Cornell University.

    A hydraulic lift

    The group’s tree-inspired work grew out of a project on hydraulic robots powered by pumping fluids. Hosoi was interested in designing hydraulic robots at the small scale, that could perform actions similar to much bigger robots like Boston Dynamic’s Big Dog, a four-legged, Saint Bernard-sized robot that runs and jumps over rough terrain, powered by hydraulic actuators.

    “For small systems, it’s often expensive to manufacture tiny moving pieces,” Hosoi says. “So we thought, ‘What if we could make a small-scale hydraulic system that could generate large pressures, with no moving parts?’ And then we asked, ‘Does anything do this in nature?’ It turns out that trees do.”

    The general understanding among biologists has been that water, propelled by surface tension, travels up a tree’s channels of xylem, then diffuses through a semipermeable membrane and down into channels of phloem that contain sugar and other nutrients.

    The more sugar there is in the phloem, the more water flows from xylem to phloem to balance out the sugar-to-water gradient, in a passive process known as osmosis. The resulting water flow flushes nutrients down to the roots. Trees and plants are thought to maintain this pumping process as more water is drawn up from their roots.

    “This simple model of xylem and phloem has been well-known for decades,” Hosoi says. “From a qualitative point of view, this makes sense. But when you actually run the numbers, you realize this simple model does not allow for steady flow.”

    In fact, engineers have previously attempted to design tree-inspired microfluidic pumps, fabricating parts that mimic xylem and phloem. But they found that these designs quickly stopped pumping within minutes.

    It was Hosoi’s student Comtet who identified a third essential part to a tree’s pumping system: its leaves, which produce sugars through photosynthesis. Comtet’s model includes this additional source of sugars that diffuse from the leaves into a plant’s phloem, increasing the sugar-to-water gradient, which in turn maintains a constant osmotic pressure, circulating water and nutrients continuously throughout a tree.

    Running on sugar

    With Comtet’s hypothesis in mind, Hosoi and her team designed their tree-on-a-chip, a microfluidic pump that mimics a tree’s xylem, phloem, and most importantly, its sugar-producing leaves.

    To make the chip, the researchers sandwiched together two plastic slides, through which they drilled small channels to represent xylem and phloem. They filled the xylem channel with water, and the phloem channel with water and sugar, then separated the two slides with a semipermeable material to mimic the membrane between xylem and phloem. They placed another membrane over the slide containing the phloem channel, and set a sugar cube on top to represent the additional source of sugar diffusing from a tree’s leaves into the phloem. They hooked the chip up to a tube, which fed water from a tank into the chip.

    With this simple setup, the chip was able to passively pump water from the tank through the chip and out into a beaker, at a constant flow rate for several days, as opposed to previous designs that only pumped for several minutes.

    “As soon as we put this sugar source in, we had it running for days at a steady state,” Hosoi says. “That’s exactly what we need. We want a device we can actually put in a robot.”

    Hosoi envisions that the tree-on-a-chip pump may be built into a small robot to produce hydraulically powered motions, without requiring active pumps or parts.

    “If you design your robot in a smart way, you could absolutely stick a sugar cube on it and let it go,” Hosoi says.

    This research was supported, in part, by the Defense Advance Research Projects Agency.

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  • richardmitnick 9:48 am on March 20, 2017 Permalink | Reply
    Tags: , , Crystallites, Disorder can be good, MIT, , Pyrolysis, Vickers hardness test   

    From MIT: “Disorder can be good” 

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    March 17, 2017
    Denis Paiste

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    MIT aerospace researchers have demonstrated that some randomness in the arrangement of carbon atoms makes materials that are lighter and stronger, shown at lower right in illustration, compared to a more densely packed and tightly ordered structure, shown lower left. They formed a type of disordered graphite-like carbon material that is often called glassy carbon by “baking” a phenol-formadehyde hydrocarbon precursor at high temperature in inert gas, a process commonly known as pyrolysis. Illustration: Itai Stein

    Researchers discover that chaos makes carbon materials lighter and stronger.

    In the quest for more efficient vehicles, engineers are using harder and lower-density carbon materials, such as carbon fibers, which can be manufactured sustainably by “baking” naturally occurring soft hydrocarbons in the absence of oxygen. However, the optimal “baking” temperature for these hardened, charcoal-like carbon materials remained a mystery since the 1950s when British scientist Rosalind Franklin, who is perhaps better known for providing critical evidence of DNA’s double helix structure, discovered how the carbon atoms in sugar, coal, and similar hydrocarbons, react to temperatures approaching 3,000 degrees Celsius (5,432 degrees Fahrenheit) in oxygen-free processing. Confusion over whether disorder makes these graphite-like materials stronger, or weaker, prevented identifying the ideal “baking” temperature for more than 40 years.

    Fewer, more chaotically arranged carbon atoms produce higher-strength materials, MIT researchers report in the journal Carbon. They find a tangible link between the random ordering of carbon atoms within a phenol-formaldehyde resin, which was “baked” at high temperatures, and the strength and density of the resulting graphite-like carbon material. Phenol-formaldehyde resin is a hydrocarbon commonly known as “SU-8” in the electronics industry. Additionally, by comparing the performance of the “baked” carbon material, the MIT researchers identified a “sweet spot” manufacturing temperature: 1,000 C (1,832 F).

    “These materials we’re working with, which are commonly found in SU-8 and other hydrocarbons that can be hardened using ultraviolet [UV] light, are really promising for making strong and light lattices of beams and struts on the nanoscale, which only recently became possible due to advances in 3-D printing,” says MIT postdoc Itai Stein SM ’13, PhD ’16. “But up to now, nobody really knew what happens when you’re changing the manufacturing temperature, that is, how the structure affects the properties. There was a lot of work on structure and a lot of work on properties, but there was no connection between the two. … We hope that our study will help to shed some light on the governing physical mechanisms that are at play.”

    Stein, who is the lead author of the paper published in Carbon, led a team under professor of aeronautics and astronautics Brian L. Wardle, consisting of MIT junior Chlöe V. Sackier, alumni Mackenzie E. Devoe ’15 and Hanna M. Vincent ’14, and undergraduate Summer Scholars Alexander J. Constable and Naomi Morales-Medina.

    “Our investigations into this carbon material as a matrix for nanocomposites kept leading to more questions making this topic increasingly interesting in and of itself. Through a series of contributions, notably from MIT undergraduate researchers and Summer Scholars, a sustained investigation of several years resulted, allowing some paradoxical results in the extant literature to be resolved,” Wardle says.

    By “baking” the resin at high temperature in inert gas, a process commonly known as pyrolysis, the researchers formed a type of disordered graphite-like carbon material that is often called glassy carbon. Stein and Wardle showed that when it is processed at temperatures higher than 1,000 C, the material becomes more ordered but weaker. They estimated the strength of their glassy carbon by applying a local force and measuring their material’s ability to resist deformation. This type of measurement, which is known to engineers as the Vickers hardness test, is a highly versatile technique that can be used to study a wide variety of materials, such as metals, glasses, and plastics, and enabled the researchers to compare their findings to many well-known engineering materials that include diamond, carbon fiber composites, and metal carbides.

    The carbon atoms within the MIT researchers’ material were more chaotically organized than is typical for graphite, and this was because phenol-formaldehyde with which they started is a complicated mix of carbon-rich compounds. “Because the hydrocarbon was disordered to begin with, a lot of the disorder remains in your crystallites, at least at this temperature,” Stein explains. In fact, the presence of more complex carbon compounds in the material strengthens it by leading to three-dimensional connections that are hard to break. “Basically you get pinned at the crystallite interface, and that leads to enhanced performance,” he says.

    These high-temperature baked materials have only one carbon atom in their structure for every three in a diamond structure. “When you’re using these materials to make nanolattices, you can make the overall lattice even less dense. Future studies should be able to show how to make lighter and cheaper materials,” Stein suggests. Hydrocarbons similar to the phenol-formaldehyde studied here can also be sourced in an environmentally friendly way, he says.

    “Up until now there wasn’t really consensus about whether having a low density was good or bad, and we’re showing in this work, that having a low density is actually good,” Stein says. That’s because low density in these crystallites means more molecular connections in three dimensions, which helps the material resist shearing, or sliding apart. Because of its low density, this material compares favorably to diamond and boron nitrides for aerospace uses. “Essentially, you can use a lot more of this material and still end up saving weight overall,” Stein says.

    “This study represents sound materials science — connecting all three facets of synthesis, structure, and property — toward elucidating poorly understood scaling laws for mechanical performance of pyrolytic carbon,” says Eric Meshot, a staff scientist at Lawrence Livermore National Laboratory, who was not involved in this research. “It is remarkable that by employing routinely available characterization tools, the researchers pieced together both the molecular and nanoscale structural pictures and deciphered this counterintuitive result that more graphitization does not necessarily equal a harder material. It is an intriguing concept in and of itself that a little structural disorder can enhance the hardness.”

    “Their structural characterization proves how and why they achieve high hardness at relatively low synthesis temperatures,” Meshot adds. “This could be impactful for industries seeking to scale up production of these types of materials since heating is a seriously costly step.” The study also points to new directions for making low-density composite structures with truly transformative properties, he suggests. “For example, by incorporating the starting SU-8 resin in, on, or around other structures (such as nanotubes as the authors suggest), can we synthesize materials that are even harder or more resistant to sheer? Or composites that possibly embed additional functionality, such as sensing?” Meshot asks.

    The new research has particular relevance now because a group of German researchers showed last year in a Nature Materials paper how these materials can form highly structured nanolattices that are strong, lightweight, and are outperformed only by diamond. Those researchers processed their material at 900 C, Stein notes. “You can do a lot more optimization, knowing what the scaling is of the mechanical properties with the structure, then you can go ahead and tune the structure accordingly, and that’s where we believe there is broad implication for our work in this study,” he says.

    This work was partly supported by MIT’s Nano-Engineered Composite aerospace STructures (NECST) Consortium members Airbus Group, Boeing, Embraer, Lockheed Martin, Saab AB, ANSYS, Hexcel, and TohoTenax. Stein was supported, in part, by a National Defense Science and Engineering Graduate Fellowship.

    See the full article here .

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  • richardmitnick 4:35 pm on March 17, 2017 Permalink | Reply
    Tags: , , MIT, , Scientists make microscopes from droplets, Tunable microlenses   

    From MIT: “Scientists make microscopes from droplets” 

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    March 10, 2017
    Jennifer Chu

    1
    Researchers at MIT have devised tiny “microlenses” from complex liquid droplets, such as these pictured here, that are comparable in size to the width of a human hair. Courtesy of the researchers

    With chemistry and light, researchers can tune the focus of tiny beads of liquid.

    Liquid droplets are natural magnifiers. Look inside a single drop of water, and you are likely to see a reflection of the world around you, close up and distended as you’d see in a crystal ball.

    Researchers at MIT have now devised tiny “microlenses” from complex liquid droplets comparable in size to the width of a human hair. They report the advance this week in the journal Nature Communications.

    Each droplet consists of an emulsion, or combination of two liquids, one encapsulated in the other, similar to a bead of oil within a drop of water. Even in their simple form, these droplets can magnify and produce images of surrounding objects. But now the researchers can also reconfigure the properties of each droplet to adjust the way they filter and scatter light, similar to adjusting the focus on a microscope.

    The scientists used a combination of chemistry and light to precisely shape the curvature of the interface between the internal bead and the surrounding droplet. This interface acts as a kind of internal lens, comparable to the compounded lens elements in microscopes.

    “We have shown fluids are very versatile optically,” says Mathias Kolle, the Brit and Alex d’Arbeloff Career Development Assistant Professor in MIT’s Department of Mechanical Engineering. “We can create complex geometries that form lenses, and these lenses can be tuned optically. When you have a tunable microlens, you can dream up all sorts of applications.”

    For instance, Kolle says, tunable microlenses might be used as liquid pixels in a three-dimensional display, directing light to precisely determined angles and projecting images that change depending on the angle from which they are observed. He also envisions pocket-sized microscopes that could take a sample of blood and pass it over an array of tiny droplets. The droplets would capture images from varying perspectives that could be used to recover a three-dimensional image of individual blood cells.

    “We hope that we can use the imaging capacity of lenses on the microscale combined with the dynamically adjustable optical characteristics of complex fluid-based microlenses to do imaging in a way people have not done yet,” Kolle says.

    Kolle’s MIT co-authors are graduate student and lead author Sara Nagelberg, former postdoc Lauren Zarzar, junior Natalie Nicolas, former postdoc Julia Kalow, research affiliate Vishnu Sresht, professor of chemical engineering Daniel Blankschtein, professor of mechanical engineering George Barbastathis, and John D. MacArthur Professor of Chemistry Timothy Swager. Moritz Kreysing and Kaushikaram Subramanian of the Max Planck Institute of Molecular Cell Biology and Genetics are also co-authors.

    Shaping a curve

    The group’s work builds on research by Swager’s team, which in 2015 reported a new way to make and reconfigure complex emulsions. In particular, the team developed a simple technique to make and control the size and configuration of double emulsions, such as water that was suspended in oil, then suspended again in water. Kolle and his colleagues used the same techniques to make their liquid lenses.

    They first chose two transparent fluids, one with a higher refractive index (a property that relates to the speed at which light travels through a medium), and the other with a lower refractive index. The contrast between the two refractive indices can contribute to a droplet’s focusing power. The researchers poured the fluids into a vial, heated them to a temperature at which the fluids would mix, then added a water-surfactant solution. When the liquids were mixed rapidly, tiny emulsion droplets formed. As the mixture cooled, the fluids in each of the droplets separated, resulting in droplets within droplets.

    To manipulate the droplets’ optical properties, the researchers added certain concentrations and ratios of various surfactants — chemical compounds that lower the interfacial tension between two liquids. In this case, one of the surfactants the team chose was a light-sensitive molecule. When exposed to ultraviolet light this molecule changes its shape, which modifies the tension at the droplet-water interfaces and the droplet’s focusing power. This effect can be reversed by exposure to blue light.

    “We can change focal length, for example, and we can decide where an image is picked up from, or where a laser beam focuses to,” Kolle says. “In terms of light guiding, propagation, and tailoring of light flow, it’s really a good tool.”

    Optics on the horizon

    Kolle and his colleagues tested the properties of the microlenses through a number of experiments, including one in which they poured droplets into a shallow plate, placed under a stencil, or “photomask,” with a cutout of a smiley face. When they turned on an overhead UV lamp, the light filtered through the holes in the photomask, activating the surfactants in the droplets underneath. Those droplets, in turn, switched from their original, flat interface, to a more curved one, which strongly scattered light, thereby generating a dark pattern in the plate that resembled the photomask’s smiley face.

    The researchers also describe their idea for how the microlenses might be used as pocket-sized microscopes. They propose forming a microfluidic device with a layer of microlenses, each of which could capture an image of a tiny object flowing past, such as a blood cell. Each image would be captured from a different perspective, ultimately allowing recovery of information about the object’s three-dimensional shape.

    “The whole system could be the size of your phone or wallet,” Kolle says. “If you put some electronics around it, you have a microscope where you can flow blood cells or other cells through and visualize them in 3-D.”

    He also envisions screens, layered with microlenses, that are designed to refract light into specific directions.

    “Can we project information to one part of a crowd and different information to another part of crowd in a stadium?” Kolle says. “These kinds of optics are challenging, but possible.”

    This research was supported, in part, by the National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, and the Max Planck Society.

    See the full article here .

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  • richardmitnick 10:26 am on March 16, 2017 Permalink | Reply
    Tags: , , , , , MIT   

    From MIT: “Scientists identify a black hole choking on stardust” 

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    March 14, 2017
    Jennifer Chu

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    In this artist’s rendering, a thick accretion disk has formed around a supermassive black hole following the tidal disruption of a star that wandered too close. Stellar debris has fallen toward the black hole and collected into a thick chaotic disk of hot gas. Flashes of X-ray light near the center of the disk result in light echoes that allow astronomers to map the structure of the funnel-like flow, revealing for the first time strong gravity effects around a normally quiescent black hole.
    Image: NASA/Swift/Aurore Simonnet, Sonoma State University

    Data suggest black holes swallow stellar debris in bursts.

    In the center of a distant galaxy, almost 300 million light years from Earth, scientists have discovered a supermassive black hole that is “choking” on a sudden influx of stellar debris.

    In a paper published today in Astrophysical Journal Letters, researchers from MIT, NASA’s Goddard Space Flight Center, and elsewhere report on a “tidal disruption flare” — a dramatic burst of electromagnetic activity that occurs when a black hole obliterates a nearby star. The flare was first discovered on Nov. 11, 2014, and scientists have since trained a variety of telescopes on the event to learn more about how black holes grow and evolve.

    The MIT-led team looked through data collected by two different telescopes and identified a curious pattern in the energy emitted by the flare: As the obliterated star’s dust fell into the black hole, the researchers observed small fluctuations in the optical and ultraviolet (UV) bands of the electromagnetic spectrum. This very same pattern repeated itself 32 days later, this time in the X-ray band.

    The researchers used simulations of the event performed by others to infer that such energy “echoes” were produced from the following scenario: As a star migrated close to the black hole, it was quickly ripped apart by the black hole’s gravitational energy. The resulting stellar debris, swirling ever closer to the black hole, collided with itself, giving off bursts of optical and UV light at the collision sites. As it was pulled further in, the colliding debris heated up, producing X-ray flares, in the same pattern as the optical bursts, just before the debris fell into the black hole.

    “In essence, this black hole has not had much to feed on for a while, and suddenly along comes an unlucky star full of matter,” says Dheeraj Pasham, the paper’s first author and a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “What we’re seeing is, this stellar material is not just continuously being fed onto the black hole, but it’s interacting with itself — stopping and going, stopping and going. This is telling us that the black hole is ‘choking’ on this sudden supply of stellar debris.”

    Pasham’s co-authors include MIT Kavli postdoc Aleksander Sadowski and researchers from NASA’s Goddard Space Flight Center, the University of Maryland, the Harvard-Smithsonian Center for Astrophysics, Columbia University, and Johns Hopkins University.

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  • richardmitnick 4:19 pm on March 8, 2017 Permalink | Reply
    Tags: , MIT, ozy.com, , Sabrina Pasterski,   

    From MIT and Harvard via ozy.com: Women in Stem “This Millennial Might Be the New Einstein” Sabrina Pasterski 

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    JAN 12 2016
    Farah Halime

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    Sabrina Pasterski

    Her research could change our understanding of the fundamentals as we know them.

    One of the things the brilliant minds at MIT do — besides ponder the nature of the universe and build sci-fi gizmos, of course — is notarize aircraft airworthiness for the federal government. So when Sabrina Pasterski walked into the campus offices one cold January morning seeking the OK for a single-engine plane she had built, it might have been business as usual. Except that the shaggy-haired, wide-eyed plane builder before them was just 14 and had already flown solo. “I couldn’t believe it,” recalls Peggy Udden, an executive secretary at MIT, “not only because she was so young, but a girl.”

    OK, it’s 2016, and gifted females are not exactly rare at MIT; nearly half the undergrads are women. But something about Pasterski led Udden not just to help get her plane approved, but to get the attention of the university’s top professors. Now, eight years later, the lanky, 22-year-old Pasterski is already an MIT graduate and Harvard Ph.D. candidate who has the world of physics abuzz. She’s exploring some of the most challenging and complex issues in physics, much as Stephen Hawking and Albert Einstein (whose theory of relativity just turned 100 years old) did early in their careers. Her research delves into black holes, the nature of gravity and spacetime. A particular focus is trying to better understand “quantum gravity,” which seeks to explain the phenomenon of gravity within the context of quantum mechanics. Discoveries in that area could dramatically change our understanding of the workings of the universe.

    She’s also caught the attention of some of America’s brightest working at NASA. Also? Jeff Bezos, founder of Amazon.com and aerospace developer and manufacturer Blue Origin, who’s promised her a job whenever she’s ready. Asked by e-mail recently whether his offer still stands, Bezos told OZY: “God, yes!”

    But unless you’re the kind of rabid physics fan who’s seen her papers on semiclassical Virasoro symmetry of the quantum gravity S-matrix and Low’s subleading soft theorem as a symmetry of QED (both on approaches to understanding the shape of space and gravity and the first two papers she ever authored), you may not have heard of Pasterski. A first-generation Cuban-American born and bred in the suburbs of Chicago, she’s not on Facebook, LinkedIn or Instagram and doesn’t own a smartphone. She does, however, regularly update a no-frills website called PhysicsGirl, which features a long catalog of achievements and proficiencies. Among them: “spotting elegance within the chaos.”

    Pasterski stands out among a growing number of newly minted physics grads in the U.S. There were 7,329 in 2013, double the four-decade low of 3,178 in 1999, according to the American Institute of Physics. Nima Arkani-Hamed, a Princeton professor and winner of the inaugural $3 million Fundamental Physics Prize, told OZY he’s heard “terrific things” about Pasterski from her adviser, Harvard professor Andrew Strominger, who is about to publish a paper with physics rock star Hawking. She’s also received hundreds of thousands of dollars in grants from the Hertz Foundation, the Smith Foundation and the National Science Foundation.

    Pasterski, who speaks in frenetic bursts, says she has always been drawn to challenging what’s possible. “Years of pushing the bounds of what I could achieve led me to physics,” she says from her dorm room at Harvard. Yet she doesn’t make it sound like work at all: She calls physics “elegant” but also full of “utility.”

    Despite her impressive résumé, MIT wait-listed Pasterski when she first applied. Professors Allen Haggerty and Earll Murman were aghast. Thanks to Udden, the pair had seen a video of Pasterski building her airplane. “Our mouths were hanging open after we looked at it,” Haggerty said. “Her potential is off the charts.” The two went to bat for her, and she was ultimately accepted, later graduating with a grade average of 5.00, the school’s highest score possible.

    An only child, Pasterski speaks with some awkwardness and punctuates her e-mails with smiley faces and exclamation marks. She says she has a handful of close friends but has never had a boyfriend, an alcoholic drink or a cigarette. Pasterski says: “I’d rather stay alert, and hopefully I’m known for what I do and not what I don’t do.”

    While mentors offer predictions of physics fame, Pasterski appears well grounded. “A theorist saying he will figure out something in particular over a long time frame almost guarantees that he will not do it,” she says. And Bezos’s pledge notwithstanding, the big picture for science grads in the U.S. is challenging: The U.S. Census Bureau’s most recent American Community Survey shows that only about 26 percent of science grads in the U.S. had jobs in their chosen fields, while nearly 30 percent of physics and chemistry post-docs are unemployed. Pasterski seems unperturbed. “Physics itself is exciting enough,” she says. ”It’s not like a 9-to-5 thing. When you’re tired you sleep, and when you’re not, you do physics.”
    ________________________________________________________________________________________________________________________________________
    Sabrina Gonzalez Pasterski (born June 3, 1993) is an American physicist from Chicago, Illinois who studies string theory and high energy physics. She describes herself as “a proud first-generation Cuban-American & Chicago Public Schools alumna.” She completed her undergraduate studies at the Massachusetts Institute of Technology (MIT) and is currently a graduate student at Harvard University.

    Pasterski has made contributions in the field of gravitational memories.[9] She is best known for her concept of “the Triangle,” which connects several physical ideas.

    Pasterski was born in Chicago on June 3, 1993. She enrolled at the Edison Regional Gifted Center in 1998, and graduated from the Illinois Mathematics and Science Academy in 2010.[10]

    Pasterski holds an active interest in aviation. She took her first flying lesson in 2003, co-piloted FAA1 at EAA AirVenture Oshkosh in 2005 and started building a kit aircraft by 2006. She soloed her Cessna 150 in Canada in 2007 and certified the aircraft she had built from a kit as airworthy in 2008, with MIT’s assistance.[citation needed] Her first U.S. solo flight was in that kit aircraft in 2009 after being signed off by her CFI Jay Maynard.[citation needed]

    Pasterski’s scientific heroes include Leon Lederman, Dudley Herschbach, and Freeman Dyson, and she was drawn to physics by Jeff Bezos. She has received job offers from Blue Origin, an aerospace company founded by Amazon.com’s Jeff Bezos, and the National Aeronautics and Space Administration (NASA).

    Before focusing on high energy theory, Pasterski worked on the CMS experiment at the Large Hadron Collider. At 21, Pasterski spoke at Harvard about her concepts of “the Triangle” and “Spin Memory”, and completed “the Triangle” for EM during an invited talk at MIT’s Center for Theoretical Physics. This work has formed the basis for further work, with one 2015 paper describing it as “a recently discovered universal triangle connecting soft theorems, symmetries and memory in gauge and gravitational theories. At 22, she spoke at a Harvard Faculty Conference about whether or not those concepts should be applied to black hole hair and discussed her new method for detecting gravitational waves.

    In early 2016, a paper by Stephen Hawking, Malcolm J. Perry, and Andrew Strominger (Pasterski’s doctoral advisor of whom she was working independently at the time) titled “Soft Hair on Black Holes” cited Pasterski’s work, making hers the only one of twelve single-author papers referenced that was authored by a female scientist.[non-primary source needed] This resulted in extensive media coverage after its appearance on the arXiv and in the days leading up to it.

    Shortly after the 2016 Hawking paper was released, actor George Takei referenced Pasterski on his Twitter account with her quote, “‘Hopefully I’m known for what I do and not what I don’t do.’ A poignant sentiment.” The Steven P. Jobs Trust article included in the tweet has been shared over 527,000 times.

    International coverage of the paper and Pasterski’s work subsequently appeared in Russia Today, Poland’s Angora newspaper and DNES in the Czech Republic. In 2016, rapper Chris Brown posted a page with a video promoting Pasterski. Forbes and The History Channel ran stories about Pasterski for their audiences in Mexico and Latin America respectively. People en Español, one of the most widely read Spanish language magazines, featured Pasterski in their April 2016 print edition. [Wikipedia]

    See the full article here .

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    The Department of Physics at Harvard is large and diverse. With 10 Nobel Prize winners (see above) to its credit, the distinguished faculty of today engages in teaching and research that spans the discipline and defines its borders, and as a result Harvard is consistently one of the top-ranked physics departments in the nation.

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